A hydrochloride obtained by combining 4,4'-carbonimidoylbis(<element>N</element>,<element>N</element>-dimethylaniline) with one molar equivalent of hydrogen chloride. A fluorescent stain for demonstra
ting acid fast organisms in a method similar to the Ziehl Neelsen. It also can be used to make a fluorescent Schiff reagent. ChEBICHEBI:51876